When people ask the question “which is the best form of exercise?”, the best answer is “it depends”. It depends on what you want to accomplish with the exercise, and what functional qualities you want to improve. All musculoskeletal tissues, including muscles, require specific training to optimally develop them. Certain movement patterns are best trained with exercises that mimic such movements and activities. Muscles develop unique qualities, depending on the resistance, speed, number of repetitions, rest, range of motion and the type of contraction used with the exercise.

A person who wants to in general get more fit and healthy, be more toned, and handle activities with more ease, typically could benefit from a combination of cardiovascular training 2-5 times per week at 50-60% of maximal heart rate (unfit person) to 70-90% of maximal heart rate (fit and healthy person), and resistance/agility exercises 2-3 times per week combining balance and coordination exercises with resisted exercises performed at an intensity of 65-75% of maximal resistance (1RM) which can be performed in 2-3 sets of approximately 12-20 repetitions to fatigue, with 1-2 minutes rest. This promotes both muscular endurance, strength, and increased muscle girth. If a higher degree of strength is needed for an activity, the intensity can be raised to > 80% of maximal resistance, in 2-3 sets of 8-10 repetitions, with 2-5 minutes rest. For people with e.g. arthritic joints, it is safer to exercise in the endurance range, in sets of 22-25 repetitions which corresponds to 60-65% of maximal resistance, avoiding pain at all times.

If an activity or sport requires speed, then some exercises should be performed fast, as long as there is good coordination. Slow contraction exercise will not improve such activities. For the fit athletic person, plyometric training can be incorporated to further increase strength and quickness, which is a quick switch from eccentric (lengthening) to concentric (shortening) contraction, such as if jumping off boxes. However, this form of exercise is very taxing on our energy reserves, and must only be done 1-2 times per week, in order not to risk overuse injury.

Isometric exercise, where resistance is held without motion, can also further increase strength, primarily around the joint position where the exercise is performed at. A hold time of 20-30 seconds to much fatigue, repeated 1-3 times, corresponds to approximately 80% of maximal resistance, and 5-10 seconds to around 90% of maximal resistance, which generates a higher level of strength for the fit person.